Abstract
We present the results of a detailed many-multiplet analysis performed on a new sample of Mg ii systems observed in high quality quasar spectra obtained using the Very Large Telescope. The weighted mean value of the variation in derived from our analysis over the redshift range is . The median redshift of our sample () corresponds to a look-back time of 9.7 Gyr in the most favored cosmological model today. This gives a limit, , for the time variation of , that forms the strongest constraint obtained based on high redshift quasar absorption line systems.
- Received 12 November 2003
DOI:https://doi.org/10.1103/PhysRevLett.92.121302
©2004 American Physical Society